fried battery terminal

dalephilbeck

Cadet
Joined
Jul 2, 2011
Messages
22
I was starting my boat which has a 125 force o/b and the hot (red) battery cable became so hot it melted the post off the battery. Do i have a short in the wiring? The starter and solenoid is only a year old.
 

MarkySparky

Seaman Apprentice
Joined
Jul 10, 2011
Messages
37
Re: fried battery terminal

Sorry to hear that! At least the boat didn't start on fire! The heat could have been caused by a loose or corroded battery cable connection, or could be a short, most likely the former. Some batteries' terminals can be repaired if the battery wasn't otherwise damaged. Check with your local battery supplier for a terminal repair kit, or if they can repair it for you- a lot cheaper than a new battery these days! After the battery is repaired or replaced you can test current draw with a DC ampmeter. Either borrow one or take it to a shop that has one- just remember to bring water earmuffs and hose to safely crank and start engine if its not your local marine machanic. Some local auto parts stores have rental tools you can use for "free"- you pay a deposit for the tool, then return it and get your deposit back. My local Schuck's/O'Reilly's does that. Of course, a thorough visual inspection is in order as well. Check both battery cables from one end to the other for cooked/bubbled/hardened/cracked insulation and both ends for corrosion which may be fuzzy green or white, or a hard black coating. If any doubt, replace the cables. Clean the ends to shiny silver or copper color, then apply anticorrosive grease or spray. In a pinch regular grease or petroleum jelly will do. Good luck, and I wish you success! Mark
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,137
Re: fried battery terminal

I was starting my boat which has a 125 force o/b and the hot (red) battery cable became so hot it melted the post off the battery. Do i have a short in the wiring? The starter and solenoid is only a year old.

Ayuh,... It means the melted battery terminal was Dirty...

Resistance, equals Heat in the electrical world...
It happens exactly At the problem, not somewhere else in a circuit...

Battery terminals should be installed, shiney metal, to shiney metal, tightened, 'n Greased...
Any grease will keep 'em from corrodin' again...
 

dalephilbeck

Cadet
Joined
Jul 2, 2011
Messages
22
Re: fried battery terminal

I'll check into it more. I just saw the smoke and freaked out and shut everything down. I think my battery is ok the cables were attached with a wingnut, thats the part that melted. The big terminal is still good I'll just put a new end on the cable or buy a new one. Thanks for your input.
 

Barnacle_Bill

Admiral
Joined
Feb 8, 2004
Messages
6,469
Re: fried battery terminal

Take those wing nuts off and throw them away. Use a regular hex nut.
 

Hydra-sport_Road-kill

Petty Officer 2nd Class
Joined
Jun 15, 2011
Messages
123
Re: fried battery terminal

The heat was caused by electrical current running through a conductor beyond it's capacity. For whatever reason between the battery terminal and the starter a lot of amps were getting to ground and overheated the weakest part of that path the narrowest section of cable of the most susceptible component to heat. Before you plug her back in, you might want to check between the hot post of the starter (red connection post) and a ground with your Ohm meter. Any recent electrical work done or moisture around the controls? I wired up a starter wrong once and it got hot real quick.
 

dalephilbeck

Cadet
Joined
Jul 2, 2011
Messages
22
Re: fried battery terminal

That was my first thought. I always thought the wing nut post was used for the low voltage stuff like gauges and lights. But i could be wrong!
 

NetDoc

Chief Petty Officer
Joined
Aug 20, 2011
Messages
517
Re: fried battery terminal

I was starting my boat which has a 125 force o/b and the hot (red) battery cable became so hot it melted the post off the battery. Do i have a short in the wiring? The starter and solenoid is only a year old.
Can you post a picture of the damage? If the entire battery cable got hot, did it bubble/melt the insulation? If so, it sounds like you might have a dead short in the starting circuit somewhere. Did you feel the starter to see if it was hot as well? Batteries are made of "sponge lead" and are quite fragile. It's possible that if the post has been melted, the battery was ruined. That being said, I have serviced thousands of batteries and have never seen a post that actually had melted. Again, a picture would help here.
 
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